The purpose of the present invention is to provide a method for manufacturing a multi-core fiber preform having a high core position accuracy, a small non-circularity of the core, and a high degree of freedom in design. The manufacturing method for the multi-core fiber preform comprises: preparing n cylindrical first core rods having a radius r1, a cylindrical second core rod having a radius R1, and a cylindrical clad; setting points P11 to P1n so as to satisfy X1max-r1 R1 X1min at positions where the distances from a point a1 on straight lines that divide the end face into n pieces with the same center angle are X11 to X1n, respectively, the point a1 on the end surface of the clad being taken as a center; forming circular first holes having a radius r1 centered on the points P11 to P1n and a second circular hole having a radius R1 centered on the point a1 in the clad; inserting the first core rods and the second core rod into the first holes and the second hole, respectively, and integrating the first core rods, the second core rod, and the clad by heat treatment.
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